Mary Kay Bergman, voice-over actress, dead

(CNN) -- Mary Kay Bergman, an actress who voiced many characters from the animated "South Park" shows and other major projects, has died. She was 38.

Bergman's attorney, Robert Harrison, says she killed herself on Thursday night. A memorial is planned for later this week.

In the demanding industry of vocal characterization, Bergman was probably best known for her versatility on the "South Park" series. She voiced the characters Mrs. Cartman, Wendy Testaburger, Stan's Mom, Kenny's Mom, Mayor McDaniels, Ms. Crabtree, Principal Victoria, Shelly Marsh and Nurse Gollem for the television series. She sang almost all the parts in a song, "Blame Canada," for this year's film "South Park: Bigger, Longer & Uncut."

Since 1989, Bergman held the position of the official voice of Snow White for Disney. Sometimes credited as Shannen Cassidy, her 14-year career included voicing work in this summer's "Star Wars, Episode 1: The Phantom Menace"; the 1996 Disney film "The Hunchback of Notre Dame," in which she read Quasimodo's mother; and this year's critically acclaimed "The Iron Giant."

She was heard in more than 400 commercials. Among them: a national campaign for Mrs. Butterworth's syrup, in which she provided the lead voice, and commercials for Kellogg's Froot Loops cereal, American Express, Honda and other sponsors.

Bergman was nominated for an award this year in the 27th annual Annies, which recognize achievement in animation. Her nomination was for her work as the voice of Sheila Broflovski in "South Park: Bigger, Longer & Uncut." Other nominees in the category of vocal performance in an animated feature were Minnie Driver, Ralph Fiennes, Eli Marenthal and Suzanne Pleshette.

'She was really in the club'

Bergman is survived by her husband, Dino Andrate, and her mother, Patricia McGowan. Harrison says Bergman had shown no signs of depression, and that her death has come as a surprise to her family. "That makes it a double tragedy," he says. "They feel there was nothing they could have done."

Bergman was the voice behind most of the female characters on the animated series "South Park"

News of her death has been carried on several Web sites, including the "South Park" site, beef-cake.com. On Monday, Bergman's agency, Sutton, Barth & Vennari (SBV), ran a full-page memorial to her in Daily Variety; Disney and other companies associated with Bergman are likely to run their own tributes to the actress this week, says Rita Vennari, who runs the agency's voice-over department.

"We miss her," says Vennari, who says SBV represented Bergman for many years. "She was wonderful, there was nobody like her. There was something very special about her, with her big brown eyes and curly red hair -- she was one of a kind.

"There's a whole group of animation people so involved in the techniques and the talent of (voice-over work), and she was one. She was really in the club. At such a young age she'd already been accepted by her peers."

Although she'll likely be remembered most readily for her "South Park" work, Vennari says Bergman herself would have been unable to single out her most significant role. "She considered all her work important, that was the best thing about her. It was all important to her."

It's unknown how Bergman's death might affect the third-season episodes of "South Park," yet to be produced.